A Chicago man, who used social media to promote ISIS and encourage attacks in the West, was sentenced to 25 years in federal prison, U.S. officials said on Friday.

Ashraf Al Safoo, 41, was found guilty of conspiring to provide material support to the Islamic State through his leadership role in the Khattab Media Foundation, an online propaganda network aligned with the terrorist group, according to the U.S. Justice Department.

Prosecutors said that the organization produced and distributed pro-ISIS videos, essays and graphics designed to incite violence and recruit followers. Some posts celebrated terrorist attacks and mass shootings in the United States and urged so-called “lone wolf” operations.

In one message, Al Safoo encouraged followers to spread propaganda “to cause confusion and spread terror within the hearts of those who disbelieved.” In another, he urged supporters to “participate in the war, and spread terror.”

Authorities said that Al Safoo coordinated directly with ISIS members and amplified the group’s messaging online.

A federal judge in Chicago also ordered 10 years of supervised release following his prison term. Al Safoo, who immigrated to the United States in 2008 and became a citizen in 2013, has been in custody since his 2018 arrest.